A systematic review with meta-analysis of radiotherapy adverse events in patients with cancer and lupus erythematosus.
Authors: Maria A. Lopez-Olivo, Sehrish Qureshi, Gaurav Sharma, Rachel S. Hicklen, Jean H. Tayar, Maria E. Suarez-Almazor
Journal: Journal of Clinical Oncology (2023)

e24092 Background: Multiple reports of serious adverse events (AEs) in people with lupus erythematosus who have received radiotherapy for their cancer exist. This systematic review determined the incidence of radiotherapy-related AEs in patients with cancer and lupus and evaluated if these patients have an increased risk of AEs compared to patients without lupus. Methods: We ran a comprehensive search in 4 electronic databases until October 2022. We included studies reporting data on AEs in patients with cancer and lupus receiving radiotherapy (palliative or definitive). Two investigators independently selected studies for inclusion, extracted data, and appraised the quality of the studies. A meta-analysis was performed for acute (≤ 90 days) and late ( &gt; 90 days) AEs. Results: Ten cohort studies (6 with control groups) and 19 case reports (30 patients) met our eligibility criteria. Cohort studies reported on 126 patients with systemic, 26 with cutaneous lupus (mostly discoid), and 5 with unspecified lupus. The age of the patients ranged from 31-68. Median follow-up ranged from 1 to 12.5 years. Minimum and maximum radiation doses reported were 10 Grays and 87.6 Grays, respectively. The pooled incidence of acute AEs for patients with lupus when considering controlled and uncontrolled studies was 50% (95%CI 35%, 65%). When analyzing controlled studies only, no statistically significant differences were observed in the pooled rate of acute AEs in patients with lupus when compared to controls (Relative risk [RR] 1.2; 95%CI 0.84, 1.7). For late AEs, the pooled incidence for patients with lupus when considering controlled and uncontrolled studies was 21% (95%CI 9%, 34%). Although the pooled rate of late AEs in patients with lupus was higher compared to the control group, the difference did not reach statistical significance (RR 1.6; 95%CI 0.96, 2.8). Three cohort studies reported separate data for SLE patients regarding the type of AEs. The acute AEs reported were mucositis, pain, erythema, infection, pruritus, pulmonary embolus, and encephalopathy. The late AEs reported were hearing loss, telangectasia, alopecia, actinic keratosis, osteomyelitis, necrosis, bowel obstruction, and pneumonitis. Out of the 30 patients reported as case reports, 18 had systemic lupus, 10 cutaneous lupus (7 discoid), and 2 had lupus-like syndrome. Twenty-one cases reported acute AEs (mucositis, erythema, moist desquamation, and fibrosis) and the remaining cases did not report AEs. Conclusions: Almost half of the participants in the included studies reported acute AEs. Although, no statistically significant differences were observed between the lupus erythematosus and control groups, caution is advised given the possible severity of AEs in lupus patients. As most publications were old additional controlled studies are needed comparing the rates of severe AEs in this population with controls.